Debt (Maturities) (Details) - USD ($) $ in Millions	Sep. 30, 2021	Dec. 31, 2020
Scheduled maturities of debt
Total installments of debt	$ 7,002	$ 7,376
Total Installments
Scheduled maturities of debt
2022	586
2023	858
2024	617
2025	670
2026	1,435
Thereafter	3,260
Total installments of debt	7,426
Total debt-related balances, net	(78)
Total carrying amount of debt	7,348
Principal installments
Scheduled maturities of debt
2022	510
2023	782
2024	540
2025	593
2026	1,357
Thereafter	3,220
Total installments of debt	7,002
Other installments
Scheduled maturities of debt
2022	76
2023	76
2024	77
2025	77
2026	78
Thereafter	40
Total installments of debt	$ 424

Amount, before unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt.

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